#include "Config.h"
#include "Base64.h"

static const char *g_pCodes = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";

static const unsigned char g_pMap[256] =
{
	255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 62, 255, 255, 255, 63,
	52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 255, 255,
	255, 254, 255, 255, 255, 0, 1, 2, 3, 4, 5, 6,
	7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,
	19, 20, 21, 22, 23, 24, 25, 255, 255, 255, 255, 255,
	255, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,
	37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
	49, 50, 51, 255, 255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
	255, 255, 255, 255
};
CBase64::CBase64()
{
}
CBase64::~CBase64()
{
}
bool CBase64::Encode(const unsigned char *pIn, unsigned long uInLen, unsigned char *pOut, unsigned long *uOutLen)
{
	unsigned long i, len2, leven;
	unsigned char *p;
	if (pOut == NULL || *uOutLen == 0)
		return false;
	//ASSERT((pIn != NULL) && (uInLen != 0) && (pOut != NULL) && (uOutLen != NULL));
	len2 = ((uInLen + 2) / 3) << 2;
	if ((*uOutLen) < (len2 + 1)) return false;
	p = pOut;
	leven = 3 * (uInLen / 3);
	for (i = 0; i < leven; i += 3)
	{
		*p++ = g_pCodes[pIn[0] >> 2];
		*p++ = g_pCodes[((pIn[0] & 3) << 4) + (pIn[1] >> 4)];
		*p++ = g_pCodes[((pIn[1] & 0xf) << 2) + (pIn[2] >> 6)];
		*p++ = g_pCodes[pIn[2] & 0x3f];
		pIn += 3;
	}
	if (i < uInLen)
	{
		unsigned char a = pIn[0];
		unsigned char b = ((i + 1) < uInLen) ? pIn[1] : 0;
		unsigned char c = 0;
		*p++ = g_pCodes[a >> 2];
		*p++ = g_pCodes[((a & 3) << 4) + (b >> 4)];
		*p++ = ((i + 1) < uInLen) ? g_pCodes[((b & 0xf) << 2) + (c >> 6)] : '=';
		*p++ = '=';
	}
	*p = 0; // Append NULL byte
	*uOutLen = p - pOut;
	return true;
}
bool CBase64::Encode(const unsigned char *pIn, unsigned long uInLen, string& strOut)
{
	unsigned long i, len2, leven;
	strOut = "";
	//ASSERT((pIn != NULL) && (uInLen != 0) && (pOut != NULL) && (uOutLen != NULL));
	len2 = ((uInLen + 2) / 3) << 2;
	//if((*uOutLen) < (len2 + 1)) return false;
	//p = pOut;
	leven = 3 * (uInLen / 3);
	for (i = 0; i < leven; i += 3)
	{
		strOut += g_pCodes[pIn[0] >> 2];
		strOut += g_pCodes[((pIn[0] & 3) << 4) + (pIn[1] >> 4)];
		strOut += g_pCodes[((pIn[1] & 0xf) << 2) + (pIn[2] >> 6)];
		strOut += g_pCodes[pIn[2] & 0x3f];
		pIn += 3;
	}
	if (i < uInLen)
	{
		unsigned char a = pIn[0];
		unsigned char b = ((i + 1) < uInLen) ? pIn[1] : 0;
		unsigned char c = 0;
		strOut += g_pCodes[a >> 2];
		strOut += g_pCodes[((a & 3) << 4) + (b >> 4)];
		strOut += ((i + 1) < uInLen) ? g_pCodes[((b & 0xf) << 2) + (c >> 6)] : '=';
		strOut += '=';
	}
	//*p = 0; // Append NULL byte
	//*uOutLen = p - pOut;
	return true;
}
bool CBase64::Decode(const string& strIn, unsigned char *pOut, unsigned long *uOutLen)
{
	unsigned long t, x, y, z;
	unsigned char c;
	unsigned long g = 3;
	//ASSERT((pIn != NULL) && (uInLen != 0) && (pOut != NULL) && (uOutLen != NULL));
	for (x = y = z = t = 0; x < strIn.length(); x++)
	{
		c = g_pMap[strIn[x]];
		if (c == 255) continue;
		if (c == 254) { c = 0; g--; }
		t = (t << 6) | c;
		if (++y == 4)
		{
			if ((z + g) > *uOutLen) { return false; } // Buffer overflow
			pOut[z++] = (unsigned char)((t >> 16) & 255);
			if (g > 1) pOut[z++] = (unsigned char)((t >> 8) & 255);
			if (g > 2) pOut[z++] = (unsigned char)(t & 255);
			y = t = 0;
		}
	}
	*uOutLen = z;
	return true;
}